Stabilizing Cu³⁺ Active Center by Intramolecular Electron Transfer for Boosting Complete Glucose Electrooxidation

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Electrocatalysts are crucial for glucose electro-conversion in sensing applications.
• Instability of catalytic active centers leads to inactivation and incomplete glucose oxidation.

Purpose of the Study:

• To develop a stable electrocatalyst for complete glucose electrooxidation.
• To enhance glucose sensing performance through catalyst design.

Main Methods:

• Synthesis of single-atom Pt-doped Cu-based MOFs (CuO-MOF-Pt1).
• Electrochemical characterization and glucose electrooxidation reaction (GOR) studies.
• Operando spectroscopy and computational analysis.
• Fabrication of a miniaturized glucose sensor.

Main Results:

• CuO-MOF-Pt1 exhibits stable high-valence Cu sites (Cu3+) responsible for complete GOR.
• Achieved a high current response and sensitivity (2.587 mA mM-1 cm-2) with a low detection limit (0.93 µM).
• Demonstrated extraordinary durability and successful application in a miniaturized saliva glucose sensor.

Conclusions:

• Single-atom Pt doping in Cu-based MOFs stabilizes active Cu3+ sites for efficient glucose electrooxidation.
• The electronic structure regulation strategy provides a new avenue for designing advanced electrocatalysts.
• The developed sensor shows promise for accurate and durable glucose detection in biological samples.